Developmental Stages of Ovule and Megagametophyte in Chenopodium botrys L. (Chenopodiaceae)

Authors : Abdolkarim Chehregani, Behrouz Malayeri, Nafiseh Yousefi

Pages : 75-81

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Publication Date : 9999-12-31

Article Type : Makaleler

Abstract :The ovule ontogenesis and the megasporogenesis stages in Chenopodium botrys L. were studied with light microscopy. Flowers and young pods were removed from natural plants and fixed in FAA 70, stored in 70% ethanol, embedded in paraffin, and sectioned at 7 µm with a microtome. Staining was carried out with Hematoxylin and Eosin and developmental stages of ovule were studied. The results of this research showed that ovule development, including megasporogenesis and initial stages of megagametogenesis, occurred while flowers were still in bud. In C. botrys the female gametophyte has a monosporic origin and the developmental pattern exhibited by this species is referred to as the polygonum type. Development of ovule starts with the formation of a primordium. In this primordium, an archesporial cell produces a megaspore mother cell, which undergoes meiosis, forming a linear tetrad. The micropylar cell is a functional megaspore that survives and will function in megagametophyte development. The mature gametophyte is composed of 7 cells: 1 secondary nucleus, 2 synergids, 1 egg cell, and 3 antipodal cells.
Keywords : Chenopodium botrys, embryo sac, megagametogenesis, megasporogenesis, ovule development, Chenopodiaceae